Single-acting engine



(No Model.)`

SINGLE ACTING ENG1`-t 'ma nomma versus 00 immuun@ msumsvau, u. c.

UNITED STATES PATENT EEICE.

JAMES P. TIDVELL, OF EVING, INDIANA.

SINGLE-ACTING ENGINE.

SPECIFICATION forming part of Letters Patent No. 426,421, dated April 22, 1890. Application filed Uctober 28, 1889. Serial No. 328,499. (No model.)

To M Z 'whom t may concern.-

Be 1t known that I, JAMES P. TIDWELL, of Ewing, county of Jackson, and State of Indiana, have invented certain new and useful Improvements in Single-Acting Engines; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, in which like letters refer to like parts.

My invention relates to the construction of engines which, though intended principally for water, may be driven by gas, water, or steam, and will be understood from the following description.

In the drawings, Figure 1 is a side View of my device, partly in section. Fig. 2 is a top view, partly broken away, showing one end of the valve and the corresponding port in that end of the steam-chest.

In detail my. device consists of a pair of cylinders c, the upper open end of which is bolted directly to the bottom of the steamchest, so that the port of the steam-chest will open centrally into such cylinder. The lower ends of these cylinders are open, and exhaustports as many as desired, are formed through the cylinder just above the point where the top of the piston would reach when it is at that end of its stroke, thus providing for the free exhaust of the motive power at the end of the cylinder opposite to that from which it enters. By this arrangement it will be seen that whether steam, gas, or water is used it only travels in one direction, escaping from the cylinder at the opposite end from which it enters, and consequently there can be no such thing as back-pressure, thereby greatly increasing the speed at which the pistons may move in the cylinders. Where Water is used, larger exhaust-ports are necessary than where gas or steam is applied.

sc is the steam-chest, which is mounted directly on the top of the cylinders and bolted thereto, as-shown in Fig. l, havingports which open centrally into the cylinders beneath, as hereinbefore mentioned.

o is a valve, which slides horizontally in the steam chest and is adapted to alternately cover and uncover the ports, and is actuated by means of a crank cr, which passes through the steam-chest and is connected directly to the valve. This crank is in turn connected to the rod r', which is pivoted to the crank cri', connected to the shaft or the axle of the working-beam b, and the ends of this working-beam are pivotally connected to the rods pr, which operate the pistons. I

0T2 is another crank, from which the rod r leads to the mechanism to be driven.

If steam is used for driving my engine, it is admitted directly from the steam chest through the ports directly upon the upper end of the piston, and this is at its highest limit when the valve is opened to admit the steam, so that the full force of the steam when in its best condition is exerted directly upon the piston, and none of the power is thereby lost, but all is saved. As the piston moves downward under the pressure of the steam the reciprocal action of the working-beam operates to force the other piston upward, "and when one piston has reached its downward limit the other has reached its upward, and is in a position directly below the port on that side, which is at the same instant opened and the steam in the chest is admitted upon the second piston, forcing that downward in turn. The exhaust-ports .fr at the other end of the cylinders are located in such position that the steam or water will readily and fully eX- haust and escape from the cylinder as the piston on that side reaches the end of its stroke, and as steam or Water is admitted only at one end of the cylinder, no back-pressure results, as in the case of ordinary cylinders where the steam is admitted alternately in both ends, or where the steam is obliged to escape and exhaust'through the same port where it enters.

It will be observed that in my device the cut-oft is accomplished directly at the top instead of thecenter of the cylinder, as in the case of ordinary engines, and all dry steam between the valve and the cylinder remains in the steam-chest, and is thus saved and ready for operation at the other end of the machine.

Of course it will be understood that the steam is admitted to the steam-chest through the pipe at the top, as shown in Fig. l.

I do not broadly claim an engine having open-ended cylinders, nor the construction IOO Where the eXhaust is formed midway in the sides thereof; but I am not aware that an engine substantially embodying the construction herein shown and described has been previously known or used.

What I claim as my invention, and desire to secure by Letters Patent, is the following:

A single-acting engine comprising a pair of cylinders c, their upper ends bolted to the bottom of a steam-chest sc, having ports opening therein, the lower ends of such cylinders open and provided With exhausts x ai, pistons p2, moving therein and connected to pistonrods at one end and at the other to a Workingbeam b, such beam mounted upon an oscillating shaft s, the crank ors, connected to the rod r', the latter connected to the crank or, which is in turn connected to the slide-valve o, the steam-chest sc, having ports at each end opening into the cylinders below, in combination with means for connecting the Working-beam to the mechanism to be driven, substantially as shown and described.

In Witness whereof I have hereunto set my hand this 4th day of October, 1889.

JAMES P. TIDWELL. IVitnesses:

C. P. JAooBs, E. B. GRIFFITH. 

